shows that this case, to a certain extent, “unites that of the Cecidomyia with the parthenogenesis of the Coccidae;” the term parthenogenesis implying that the mature females of the Coccidae are capable of producing fertile eggs without the concourse of the male.

Certain animals belonging to several classes are now known to have the power of ordinary reproduction at an unusually early age; and we have only to accelerate parthenogenetic reproduction by gradual steps to an earlier and earlier age — Chironomus showing us an almost exactly intermediate stage, viz., that of the pupa — and we can perhaps account for the marvellous case of the Cecidomyia.

It has already been stated that various parts in the same individual, which are exactly alike during an early